Burgos 1334-Montiel 1369
He was an controversial figure. Cruel for some, avenging for others, he spent long seasons in Tordesillas with his favorite, Maria de Padilla, with whom he maintained an intense love relationship and with whom, as he recognized later, had married secretly.
He was born in Burgos in 1334. His parents were Alfonso XI and his legitimate wife Maria de Portugal. He always lived away from the Court together with his mother, both out of place by Eleanor de Guzmán, the King's favourite, and their illegitimate children.
In 1350, he comes to the throne when his father, Alfonso XI, dies. Until 1355, he is influenced by his mother and Juan Alonso de Alburquerque, Portuguese nobleman who enjoyed the Queen's confidence. His first act as governor to imprison and murder Eleanor de Guzmán (1351).
In 1352 he meets Maria de Padilla and they will have four children. However, he married Blanca de Borbón, niece of the king of France, and Joanna de Castro. In both cases, they were abandoned to meet Maria de Padilla.
In 1355, the Infanta Isabella was born in the "mudéjar" palace of Tordesillas. (Note: Mudéjar refers to the architectural style that flourished in Spain since the 13th century until the 16th century. Its main features are the use of Christian art elements and Arab ornamentation.) She was the third daughter of Pedro I and María de Padilla. The Infante Alfonso was born at the same place four years later. He was the only male child they had and he was stated as heir in 1362. However, he died soon afterwards. The same year, he donated the Palace to his daughter Beatriz so that she changed it into a convent.
He took economic and social measurements to put an end to the ambitions of the nobility that make Pedro I lose popularity among noblemen. His step-brother, Enrique de Trastámara, takes advantage of it in order to claim his rights to the throne. All that rouses internal struggles to seize power in Castile that finished with the murder of Pedro I in Montiel in 1369.